Also called: gears, shifter, cassette
What it does
Using the right gear saves battery and your knees. A bent derailleur or stretched cable causes poor shifting.
Signs of a problem
- Gears skip or won't shift
- Chain rubs or makes noise
Safe things to check
- Look at the derailleur from behind: it should hang straight down, not bent toward the wheel.
Looking after it
- A bent derailleur hanger is common after a fall; a shop can straighten or replace it.